The possibility of knowing the effective pressure distribution over the sail plan is of great interest for the aerodynamic and structural design of sails and for the selection and the optimal use of materials and production techniques. Integral measurements alone may not be sufficient in understanding how a sail plan can be optimized on specific purposes, if any information about the complex local fluid-structure interaction are provided.
In the last few years there has been a revival of pressure measurements on yacht sails and recently several contributions can be found in literature aiming to assess sail pressure distribution detection ([1-8]). The systems disclosed in the literature are generally set-up of scientific type and are too complex for a commercial application. Moreover, these systems are too invasive.
U.S. Pat. No. 6,826,968 discloses a device for detecting pressure at different points of a sail comprising a complex array of pressure sensing pixel capacitors arranged in two orthogonal sets of electrodes.
WO200573078 discloses an apparatus comprising two distinct measuring devices, placed windward and leeward respectively
Another system for measuring pressure on both sides of the sail is mentioned in GB2349699, but structural and functional details are not provided.
Therefore, there is the need of a system for measuring pressure on sails which is simple and suitable for commercial purposes and of low invasive impact on the sails.
There is also the need of a system capable of measuring pressure distribution on the sails at full scale.
A further need is for a system which is operable in operating conditions, namely outside laboratory environment, in particular outdoor.